Preparation

Spray grill with nonstick spray. Prepare barbecue (medium-high heat).

Brush tuna steaks, zucchini, and eggplant with olive oil; sprinkle with salt and pepper. Grill vegetables until tender and lightly charred, turning occasionally, about 12 minutes. Remove from grill and cut into bite-size chunks. Place vegetables, tomatoes, herbes de Provence, and garlic in large bowl; toss to blend. Set aside.

Grill tuna steaks to desired doneness, about 4 minutes per side for medium-rare. Place tuna on plates, top with vegetables, and serve with aioli.